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You searched for: creator:"r_garcia"
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[audio]r_garcia - Gluteus.Freq [kpu041] - r_garcia
Florida native and Nophi Recordings frontman r_garcia has so lovingly graced our presence with an album of new tunes, a full 40 minutes worth of new music exclusive to Kikapu that is. While not afraid to show his experimental side, r_garcia's music borders on a mix between melodic electronics and noise, with a surprising slice of soul and funk mixed in. One can also hear his love for indie rock shining through on these tracks, so feel free to rock out yourself to these twelve amazingly fun and b...
Downloads: 24,343 5.00 out of 5 stars5.00 out of 5 stars5.00 out of 5 stars5.00 out of 5 stars5.00 out of 5 stars(3 reviews)
[audio]r_garcia - travel by light rail [kpu070] - r_garcia
Nophi Records frontman r_garcia returns to Kikapu with another gorgeously fun EP of chiptune bleeps, beautiful melodies, and remarkable riddims. One might call this a pop-centric view of the IDM sound, whatever that may be. In essence though, it's just a wonderfully enjoyable collection of tracks that will get your booty shaking and have you grinning ear to ear.
Downloads: 1,432 5.00 out of 5 stars5.00 out of 5 stars5.00 out of 5 stars5.00 out of 5 stars5.00 out of 5 stars(3 reviews)
[audio]R_Garcia - Remover ep [lcd047] - R_Garcia
R_Garcia the head of Nophi Recordings puts together a stellar release of abstract electronics consisting of melodious travels over cerebral beats. There are a variety of styles present throughout its tracks including: IDM, Reggae, Downtempo, and Ambient. Engage your ears into an imploding universe of aural Journeys. All composition, instrumentation and sequencing by Randy Garcia except where noted...
Keywords: IDM; Melodic Downtempo
Downloads: 13,858
[texts]On the monodromy at infinity of a polynomial map, II - R. Garcia
In the last years a lot of work has been concentrated on the study of the behaviour at infinity of polynomial maps. This behaviour can be very complicated, therefore the main idea was to find special classes of polynomial maps which have, in some sense, nice properties at infinity. In this paper, we completely determine the complex algebraic monodromy at infinity for a special class of polynomial maps (which is complicated enough to show the nature of the general problem).
Downloads: 3
[texts]Gravitational perturbations of an ultrastatic wormhole - Claudia Moreno
This paper has been withdrawn by the author due to a crucial sign error in equation 1
Downloads: 3
[texts]Through a Lattice Darkly -- Shedding Light on Electron-Phonon Coupling in the High T$_c$ Cuprates - D. R. Garcia
With its central role in conventional BCS superconductivity, electron-phonon coupling has appeared to play a more subtle role in the phase diagram of the high temperature superconducting cuprates. The added complexity of the cuprates with potentially numerous competing phases including charge, spin, orbital, and lattice ordering, makes teasing out any unique phenomena challenging. In this review, we present our work using angle resolved photoemission spectroscopy (ARPES) to explore the role of t...
Downloads: 9
[texts]MO analysis of the high statistics Belle results on $γγ\to π^+π^-,π^0π^0$ with chiral constraints - R. Garcia-Martin
We reconsider Muskhelishvili-Omn\`es (MO) dispersive representations of photon-photon scattering to two pions, motivated by the very high statistics results recently released by the Belle collaboration for charged as well as neutral pion pairs and also by recent progress in the determination of the low-energy $\pi\pi$ scattering amplitude. Applicability of this formalism is extended beyond 1 GeV by taking into account inelasticity due to $K\bar{K}$ ...
Downloads: 8
[texts]Two Neutron Star SXT in Quiescence: 4U 2129+47 and EXO 0748-676 - Michael R. Garcia
We report on x-ray observations of two soft x-ray transients containing neutron stars, 4U 2129+47 and EXO 0748-676. Our emphasis is on the quiescent properties of these sources. The x-ray spectrum and lightcurve of the eclipsing Low-Mass X-ray Binary (LMXB) 4U 2129+47 was measured with the ROSAT PSPC during its current quiescent state. The quiescent x-ray luminosity of ~ 10**32.7 ergs/s and blackbody temperature of kT ~ 0.21 keV are similar to other quiescent LMXB...
Downloads: 1
[audio]Danger Of Fire - J. R. Garcia; J. Mª. Vera
SUNFIRE'S SONG Music: Juan Ramon Garcia Fuentes, Jose Maria Vera Galvan Lyrics: Jose Maria Vera Galvan
Downloads: 207
[texts]Chiral condensate thermal evolution at finite baryon chemical potential within Chiral Perturbation Theory - R. Garcia Martin
We present a model independent study of the chiral condensate evolution in a hadronic gas, in terms of temperature and baryon chemical potential. The meson-meson interactions are described within Chiral Perturbation Theory and the pion-nucleon interaction by means of Heavy Baryon Chiral Perturbation Theory, both at one loop, and nucleon-nucleon interactions can be safely neglected within our hadronic gas domain of validity...
Downloads: 1
[texts]Early Galactic Evolution of Carbon, Nitrogen and Oxygen - G. Israelian
We present results on carbon, nitrogen, and oxygen abundances for a sample of unevolved metal-poor stars with metallicities in the range -0.3[Fe/H]>-3.0, the [O/Fe] ratio increases from approximately 0 to 1. We find a good agreement between abundances based on the forbidden line, the OH and IR triplet lines when gravities based on Hipparcos} parallaxes are considered for the sample stars. Gravities derived from LTE ionization balance in metal-poor stars with [Fe/H]< -1 are likely too low, and co...
Downloads: 4
[texts]Chiral condensate thermal evolution at finite baryon chemical potential within ChPT - R. Garcia Martin
We present a model independent study of the chiral condensate evolution in a hadronic gas, in terms of temperature and baryon chemical potential. The meson-meson interactions are described within Chiral Perturbation Theory and the pion-nucleon interaction by means of Heavy Baryon Chiral Perturbation Theory, both at one loop. Together with the virial expansion, this provides a model independent systematic expansion at low temperatures and chemical potentials, which includes the physical quark mas...
Downloads: 3
[texts]Oxygen abundances in unevolved metal-poor stars from near-UV OH lines - G. Israelian
We have performed a detailed oxygen abundance analysis of 23 metal-poor (-3.0
Downloads: 5
[texts]Principal Mean Curvature Foliations on Surfaces immersed in ${\mathbb R} ^4$ - R. Garcia
Here are studied qualitative properties of the families of curves --foliations-- on a surface immersed in ${\mathbb R}^4$, along which it bends extremally in the direction of the mean normal curvature vector. Typical singularities and cycles are described, which provide sufficient conditions, likely to be also necessary, for the structural stability of the configuration of such foliations and their singularities, under small $C^3$ perturbations of the immersion...
Downloads: 5
[texts]Validity of the "sharp-kink approximation" for water and other fluids - R. Garcia
The contact angle of a liquid droplet on a solid surface is a direct measure of fundamental atomic-scale forces acting between liquid molecules and the solid surface. In this work, the validity is assessed of a simple equation, which approximately relates the contact angle of a liquid on a surface to its density, its surface tension, and the effective molecule-surface potential. This equation is derived in the sharp-kink approximation, where the density profile of the liquid is assumed to drop p...
Downloads: 4
[texts]Surfaces Around Closed Principal Curvature Lines, an Inverse Problem - R. Garcia
Given a non circular spacial closed curve whose total torsion is an integer multiple of $2\pi$, we construct a germ of a smooth surface that contains it as a hyperbolic principal cycle.
Downloads: 8
[texts]Norm estimates of complex symmetric operators applied to quantum systems - Emil Prodan
This paper communicates recent results in theory of complex symmetric operators and shows, through two non-trivial examples, their potential usefulness in the study of Schr\"odinger operators. In particular, we propose a formula for computing the norm of a compact complex symmetric operator. This observation is applied to two concrete problems related to quantum mechanical systems. First, we give sharp estimates on the exponential decay of the resolvent and the single-particle density matrix for...
Downloads: 5
[texts]Thin-thick coexistence behavior of 8CB liquid crystalline films on silicon - R. Garcia
The wetting behavior of thin films of 4'-n-octyl-4-cyanobiphenyl (8CB) on Si is investigated via optical and x-ray reflectivity measurement. An experimental phase diagram is obtained showing a broad thick-thin coexistence region spanning the bulk isotropic-to-nematic ($T_{IN}$) and the nematic-to-smectic-A ($T_{NA}$) temperatures. For Si surfaces with coverages between 47 and $72\pm3$ nm, reentrant wetting behavior is observed twice as we increase the temperature, with separate coexistence behav...
Downloads: 6
[texts]Critical Casimir force in $^4$He films: confirmation of finite-size scaling - A. Ganshin
We present new capacitance measurements of critical Casimir force-induced thinning of $^4$He films near the superfluid/normal transition, focused on the region below $T_{\lambda}$ where the effect is the greatest. $^4$He films of 238, 285, and 340 \AA thickness are adsorbed on N-doped silicon substrates with roughness $\approx 8 {\AA}$. The Casimir force scaling function $\vartheta $, deduced from the thinning of these three films, collapses onto a single universal curve, attaining a minimum $\v...
Downloads: 2
[texts]Intelligent Agents: A Physics Education Opportunity in Latin-America - D. Sanchez-Guzman
Intelligent Agents are being applied in a wide range of processes and everyday applications. Their development is not new, in recent years they have had an increased attention and design in learning and as mentoring tools. In this paper we discuss the definition of what an intelligent agent is; how they are applied; how thy look like; recent implementations of agents; agents as support in learning process; their state in Latin-American countries and future developments and trends that will permi...
Downloads: 3
[texts]Reinstating the M31 X-ray system RX J0042.3+4115 as a black hole X-ray binary, and compelling evidence for an extended corona - R. Barnard
The M31 X-ray source RX J0042.3+4115 was originally identified as a black hole binary because it displayed characteristic low state variability at conspicuously high luminosities; unfortunately, this variability was later found to be artificial. However, analysis of 84 Chandra ACIS observations, an HST ACS/WFC observation, and a 60 ks XMM-Newton observation has supplied new evidence that RX J0042.3+4115 is indeed a black hole binary...
Downloads: 2
[texts]Injective representations of infinite quivers. Applications - E. Enochs
In this article we study injective representations of infinite quivers. We classify the indecomposable injective representations of trees and then describe Gorenstein injective and projective representations of barren trees.
Downloads: 2
[texts]Experimental status of the $ππ$ isoscalar S wave at low energy: $f_0(600)$ pole and scattering length - F. J. Yndurain
The experimental results obtained in the last few years on kaon decays (K$\to2\pi$ and, above all, Ke4 decays) allow a reliable, model independent determination of low energy $\pi\pi$ scattering in the S0 wave. Using them and, eventually, other sets of data, it is possible to give a precise parametrization of the S0 wave as well as to find the scattering length and effective range parameter. One can also perform an extrapolation to the pole of the "$\sigma$ resonance" [$f_0(600)$]...
[texts]Heisenberg-limited eavesdropping on the continuous-variable quantum cryptographic protocol with no basis switching is impossible - J. Sudjana
The Gaussian quantum key distribution protocol based on coherent states and heterodyne detection [Phys. Rev. Lett. 93, 170504 (2004)] has the advantage that no active random basis switching is needed on the receiver's side. Its security is, however, not very satisfyingly understood today because the bounds on the secret key rate that have been derived from Heisenberg relations are not attained by any known scheme...
Downloads: 1
[texts]Inductive Lusternik-Schnirelmann category in a model category - J. M. Garcia-Calcines
We introduce the notion of inductive category in a model category and prove that it agrees with the Ganea approach given by Doeraene. This notion also coincides with the topological one when we consider the category of (well-) pointed topological spaces.
[texts]Loophole-free test of quantum non-locality using high-efficiency homodyne detectors - R. Garcia-Patron
We provide a detailed analysis of the recently proposed setup for a loophole-free test of Bell inequality using conditionally generated non-Gaussian states of light and balanced homodyning. In the proposed scheme, a two-mode squeezed vacuum state is de-gaussified by subtracting a single photon from each mode with the use of an unbalanced beam splitter and a standard low-efficiency single-photon detector...
Downloads: 3
[texts]Locally projective monoidal model structure for complexes of quasi-coherent sheaves on P^1(k) - Edgar Enochs
We will generalize the projective model structure in the category of unbounded complexes of modules over a commutative ring to the category of unbounded complexes of quasi-coherent sheaves over the projective line. Concretely we will define a locally projective model structure in the category of complexes of quasi-coherent sheaves on the projective line. In this model structure the cofibrant objects are the dg-locally projective complexes...
Downloads: 3
[texts]Time-resolved Spectroscopy of the M15 X-ray Binary AC211/X2127+119 - M. A. P. Torres
We present time-resolved spectroscopy acquired during two epochs (spaced apart by ~15 days) of the eclipsing Low Mass X-ray Binary AC211/X2127+119 in the globular cluster M15. The spectra show variations in the HeII 4686 emission line not only modulated on the orbital period, but also on time-scales of a few days. During the first epoch of observation, the emission line shows a strong S-wave superimposed on the average double-peaked profile...
Downloads: 2
[texts]Certainty relations between local and nonlocal observables - R. Garcia Diaz
We demonstrate that for an arbitrary number of identical particles, each defined on a Hilbert-space of arbitrary dimension, there exists a whole ladder of relations of complementarity between local, and every conceivable kind of joint (or nonlocal) measurements. E.g., the more accurate we can know (by a measurement) some joint property of three qubits (projecting the state onto a tripartite entangled state), the less accurate some other property, local to the three qubits, become...
Downloads: 3
[texts]Precise dispersive data analysis of the f0(600) pole - R. Garcia-Martin
We review how the use of recent precise data on kaon decays together with forward dispersion relations (FDR) and Roy's equations allow us to determine the sigma resonance pole position very precisely, by using only experimental input. In addition, we present preliminary results for a modified set of Roy-like equations with only one subtraction, that show a remarkable improvement in the precision around the sigma region...
Downloads: 6
[texts]Chandra identification of 26 new black hole candidates in the central region of M31 - R. Barnard
We have previously identified 10 M31 black hole candidates (BHCs) in M31, from their X-ray properties alone. They exhibit "hard state" emission spectra that are seen at luminosities < ~10% Eddington in X-ray binaries (XBs) containing a neutron star (NS) or black hole (BH), at luminosities that significantly exceed the NS threshold. Nine of these are associated with globular clusters (GCs); hence, these are most likely low mass X-ray binaries (LMXBs); eight are included in this survey...
Downloads: 3
[texts]Sigma pole position and errors of a once and twice subtracted dispersive analysis of pi-pi scattering data - R. Kaminski
We show how the new precise data on kaon decays together with forward dispersion relations, sum rules and once- and twice-subtracted Roy's equations allow for a precise determination of the sigma meson pole position. We present a comparison and a study of the different sources of uncertainties when using either once- or twice-subtracted Roy's equations to analyze the data. Finally we present a preliminary determination of the sigma pole from the constrained dispersive data analysis.
Downloads: 6
[texts]A deterministic cavity-QED source of polarization entangled photon pairs - R. Garcia-Maraver
We present two cavity quantum electrodynamics proposals that, sharing the same basic elements, allow for the deterministic generation of entangled photons pairs by means of a three-level atom successively coupled to two single longitudinal mode high-Q optical resonators presenting polarization degeneracy. In the faster proposal, the three-level atom yields a polarization entangled photon pair via two truncated Rabi oscillations, whereas in the adiabatic proposal a counterintuitive Stimulated Ram...
Downloads: 2
[texts]Cavity-QED entangled photon source based on two truncated Rabi oscillations - R. Garcia-Maraver
We discuss a cavity-QED scheme to deterministically generate entangled photons pairs by using a three-level atom successively coupled to two single longitudinal mode high-Q cavities presenting polarization degeneracy. The first cavity is prepared in a well defined Fock state with two photons with opposite circular polarizations while the second cavity remains in the vacuum state. A half-of-a-resonant Rabi oscillation in each cavity transfers one photon from the first to the second cavity, leavin...
Downloads: 3
[texts]Precise determination of the sigma pole location from a dispersive analysis - R. Garcia-Martin
We review how the use of recent precise data on kaon decays together with forward dispersion relations (FDR) and Roy's equations allow us to determine the sigma resonance pole position very precisely, by using only experimental input. In addition, we present preliminary results for a modified set of Roy-like equations with only one subtraction, that show a remarkable improvement in the precision around the sigma resonance region...
Downloads: 11
[texts]X-ray Novae and the Evidence for Black Hole Event Horizons - Ramesh Narayan
We discuss new observations of X-ray novae which provide strong evidence that black holes have event horizons. Optical observations of 13 X-ray novae indicate that these binary stars contain collapsed objects too heavy to be stable neutron stars. The objects have been identified as black hole candidates. X-ray observations of several of these X-ray novae in quiescence with the Chandra X-ray Observatory show that the systems are approximately 100 times fainter than nearly identical X-ray novae co...
Downloads: 13
[texts]Gorenstein categories and Tate cohomology on projective schemes - Edgar Enochs
We study Gorenstein categories. We show that such a category has Tate cohomological functors and Avramov-Martsinkovsky exact sequences connecting the Gorenstein relative, the absolute and the Tate cohomological functors. We show that such a category has what Hovey calls an injective model structure and also a projective model structure in case the category has enough projectives. As examples we show that if X is a locally Gorenstein projective scheme then the category Qco(X) of quasi-coherent sh...
Downloads: 2
[texts]Accretion Rates in Herbig Ae stars - R. Garcia Lopez
Accretion rates from disks around pre-main sequence stars are of importance for our understanding of planetary formation and disk evolution. We provide in this paper estimates of the mass accretion rates in the disks around a large sample of Herbig Ae stars. We obtained medium resolution 2 micron spectra and used the results to compute values of Macc from the measured luminosity of the Br_gamma emission line, using a well established correlation between L(Br_gamma) and the accretion luminosity L...
Downloads: 8
[texts]IR diagnostics of embedded jets: velocity resolved observations of the HH34 and HH1 jets - R. Garcia Lopez
We present VLT-ISAAC medium resolution spectroscopy of the HH34 and HH1 jets. Our aim is to derive the kinematics and the physical parameters and to study how they vary with jet velocity. We use several important diagnostic lines such as [FeII] 1.644um, 1.600um and H2 2.122um. In the inner jet region of HH34 we find that both the atomic and molecular gas present two components at high and low velocity...
Downloads: 4
[texts]Timing and Spectral Analysis of the Unusual X-Ray Transient XTE J0421+560/CI Camelopardalis - E. S. Bartlett
We present a detailed X-ray study of the 2003 XMM-Newton observation of the High Mass X-ray Binary XTE J0421+560/CI Cam. The continuum of the X-ray spectrum is well described by a flat power law (Gamma=1.0+/-0.2) with a large intrinsic absorbing column (N_H=(4.4+/-0.5)\times10^{23} cm^{-2}). We have decomposed the broad iron line into 3 separate components: Fe\textsc{i}-K$\alpha$, Fe\textsc{i}-K$\beta$ and Fe\textsc{xxiv-xxv}K$\alpha$...
[texts]Proposal for a loophole-free Bell test using homodyne detection - R. Garcia-Patron Sanchez
We propose a feasible optical setup allowing for a loophole-free Bell test with efficient homodyne detection. A non-gaussian entangled state is generated from a two-mode squeezed vacuum by subtracting a single photon from each mode, using beamsplitters and standard low-efficiency single-photon detectors. A Bell violation exceeding 1% is achievable with 6-dB squeezed light and an homodyne efficiency around 95%...
Downloads: 2
[texts]New Evidence for Black Hole Event Horizons from Chandra - Michael R. Garcia
Previously we claimed that Black Hole X-ray Novae (BHXN) in quiescence are much less luminous than equivalent Neutron Star X-ray Novae (NSXN). This claim was based on the quiescent detection of a single short period BHXN (A0620-00, P(orb)=7.8 hrs) and two longer period BHXN (GRO J1655-40, P(orb)=62.9 hrs; V404 Cyg, P(orb)=155.3 hrs), along with sensitive upper limits. We announce the detection of two more short period BHXN (GRO J0422+32, P(orb)=5.1 hrs; GS 2000+25, P(orb)=8.3 hrs), an upper limi...
[texts]A Black Hole of > 6 Solar Masses in the X-ray Nova XTE J1118+480 - J. E. McClintock
Observations of the quiescent X-ray nova XTE J1118+480 with the new 6.5-m MMT have revealed that the velocity amplitude of the dwarf secondary is 698 +/- 14 km/s and the orbital period of the system is 0.17013 +/- 0.00010 d. The implied value of the mass function, f(M) = 6.00 +/- 0.36 solar masses, provides a hard lower limit on the mass of the compact primary that greatly exceeds the maximum allowed mass of a neutron star...
[texts]M74 X-1 (CXOU J013651.1+154547): An Extremely Variable Ultraluminous X-Ray Source - M. I. Krauss
Ultraluminous X-ray sources (ULXs) have been described variously as the most luminous normal X-ray binaries, as hypernovae, and as "intermediate-mass" black holes with masses of hundreds to thousands of solar masses. We present results on M74 X-1 (CXOU J013651.1+154547), a ULX in the nearby spiral galaxy M74 (NGC 628), from observations by Chandra and XMM-Newton. M74 X-1is a persistent source which exhibits extreme variability and changes in spectral state on timescales of several thousand secon...
[texts]On the binary nature of 1RXS J162848.1-415241 - M. A. P. Torres
We present spectroscopy of the optical counterpart to 1RXS J162848.1-41524, also known as the microquasar candidate MCQC J162847-4152. All the data indicate that this X-ray source is not a microquasar, and that it is a single-lined chromospherically active binary system with a likely orbital period of 4.9 days. Our analysis supports a K3IV spectral classification for the star, which is dominant at optical wavelengths...
Downloads: 3
[texts]Optical Constraints on an X-ray Transient Source in M31 - Benjamin F. Williams
We have detected a transient X-ray source in the M31 bulge through a continuing monitoring campaign with the Chandra ACIS-I camera. The source was detected at R.A.=00:42:33.428 +/- 0.11'', Dec.=+41:17:03.37 +/- 0.11'' in only a single observation taken 2004 May 23. Fortuitous optical HST/ACS imaging of the transient location prior to the X-ray outburst, along with follow-up HST/ACS imaging during and after the outburst, reveals no transient optical source brighter than B (equivalent) = 25.5...
Downloads: 3
[texts]Aql X-1 in Outburst and Quiescence - M. R. Garcia
We present photometry and spectroscopy of the soft x-ray transient Aql X-1. Optical photometry during an active state shows a strong (0.6 mag peak-to-peak) modulation at a period of 19 hours. Infrared (K'-band) photometry during a quiescent state limits any ellipsoidal variations to
[texts]Chandra and Hubble Study of a New Transient X-ray Source in M31 - Benjamin F. Williams
We present X-ray and optical observations of a new transient X-ray source in M31 first detected 23-May-2004 at R.A.=00:43:09.940 +/- 0.65'', Dec.=41:23:32.49 +/- 0.66''. The X-ray lightcurve shows two peaks separated by several months, reminiscent of many Galactic X-ray novae. The location and X-ray spectrum of the source suggest it is a low mass X-ray binary (LMXB). Follow-up HST ACS observations of the location both during and after the outburst provide a high-confidence detection of variabili...
[texts]Symmetry breaking and clustering in a vibrated granular gas with several macroscopically connected compartments - J. Javier Brey
The spontaneous symmetry breaking in a vibro-fluidized low-density granular gas in three connected compartments is investigated. When the total number of particles in the system becomes large enough, particles distribute themselves unequally among the three compartments. Particles tend to concentrate in one of the compartments, the other two having the (relatively small) same average number of particles...
[texts]Once subtracted Roy-like dispersion relations and a precise analysis of $ππ$ scattering data - R. Garcia-Martin
We report our progress on the data analysis of $\pi\pi$ scattering data in terms of Forward Dispersion Relations (FDR), as well as Roy equations (RE) and their once-subtracted counterpart, GKPY equations. The first part of the analysis consists of independent fits to the different $\pi\pi$ channels. The GKPY equations provide a more stringent consistency check for the parametrizations of the S0-wave data in the region from 400 to 1100 MeV, In the second part we present our preliminary analysis w...
Downloads: 3
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